A series of water-soluble poly(carboxybetaines) (poly(4-(diallyl(methyl)ammonio)butanoates), poly(DAMAB)) was synthesized. Detailed studies of the solution properties of these poly(carboxybetaines) were performed using viscometry, static and dynamic light scattering, velocity sedimentation and flow birefringence. Molar masses, other molecular parameters and conformational characteristics of the macromolecules were determined in water and 1 M NaClNaCl solutions. The Mark-Kuhn-Houwink and scaling equations were obtained for poly(DAMAB). It was established that 1 M NaCl solution is a thermodynamically good solvent for poly(DAMAB). In water, the conformation of poly(DAMAB) molecules is similar to that of a polymer coil under θ -conditions. The Kuhn segment length for poly(DAMAB) molecules was A=7nm in water and in 1 M NaCl solution. Data on the thermal stability of DAMAB and its polymer were obtained. Thorough consideration of contributions of optical effects of micro- and macroform into the observed flow biref